In general, a refrigerator is an apparatus that discharges cool air generated by a refrigerating cycle involving a compressor, a condenser, an expansion valve, and an evaporator to lower the temperature in the refrigerator such that food is stored in a frozen state or in a refrigerated state.
A refrigerator generally includes a freezing compartment for storing food or beverages in a frozen state and a refrigerating compartment for storing food or beverages in a refrigerated state.
Refrigerators are classified into a top mount type refrigerator, in which a freezing compartment is disposed above a refrigerating compartment, a bottom freezer type refrigerator, in which a freezing compartment is disposed under a refrigerating compartment, or a side by side type refrigerator, in which a freezing compartment and a refrigerating compartment are disposed side by side. In each case, doors are provided at the freezing compartment and the refrigerating compartment, respectively, such that access to the freezing compartment and the refrigerating compartment is possible through the doors.
In addition to refrigerators in which a freezing compartment and a refrigerating compartment are partitioned from each other, there are also refrigerators in which access to a freezing compartment and a refrigerating compartment is possible through a single door. Most such single door type refrigerators are small-sized, and the freezing compartment is generally provided in a specific space inside the refrigerating compartment.
There are also French type refrigerators, in which an upper refrigerating compartment is opened and closed by left and right doors, as a kind of top mount type refrigerator. A freezing compartment of the French type refrigerator may also be opened and closed by left and right doors.
In recent years, a home bar, an ice maker, a shelf, and a basket have been frequently mounted at the rear of the door of the refrigerator in order to use the rear of the door as an additional storage space or an additional functional space. That is, the door has additional functions, such as the provision of additional storage space or the production and supply of ice or cold water, in addition to simply opening and closing the freezing compartment or the refrigerating compartment.
A refrigerator having a sub door for opening and closing a sub storage compartment provided in a main door has been proposed. This type of refrigerator may be called a door in door (DID) refrigerator. When the main door is opened, a main storage compartment is used, and when the sub door is opened while the main door is closed, the sub compartment may be used.
The sub storage compartment may be disposed at the rear side of the main door and may be a storage area partially separated by a partition from the main storage compartment. An area for the sub storage compartment is formed not at part of the main door but at substantially the entire main door.
Goods that are frequently used, such as beverages, may be stored in the sub storage compartment, and the sub storage compartment includes a plurality of shelves and a plurality of baskets. Since the height of goods vary, it may be necessary to change the positions of the shelves and the baskets as occasion demands.